The 35 mm photographic still cameras that have been used for decades provide a large image area for high quality pictures, but otherwise have several serious problems. The 35 mm film strip is easily misloaded so that it does not advance in the camera. Failure to secure the leading end of the film strip so it winds on the take-up spindle is common, and it also happens that the film supply container can be canted and jammed under the camera cover to pinch the film so that the drive sprocket tears out perforations, rather than advancing the film. Since the user cannot see the film or observe its advance once the camera is closed, these errors can go undetected, and the user can operate the camera in the mistaken belief that pictures are being taken.
The 35 mm format camera also requires setting a frame counter, rewinding the film after exposure, and manually entering the film speed into the camera's exposure control system. These operations, along with manual loading and threading, all present opportunities for error. Many attempts have been made to automate some of the 35 mm camera functions, but no solution to these problems has been entirely satisfactory.
I have devised a photographic still camera and film system that afford the user an image area almost as large as 35 mm while eliminating manual operations and any chance for misloading the film in the camera. My camera and film system can accommodate any type of still camera film including transparencies compatible with existing slide mounts and projectors. Although my camera is simplified and uses more economical components for film loading and advance, the camera otherwise can use a wide variety of optical systems, shutters, and exposure control systems and can have different dimensions accommodating different operating equipment. My camera and film system greatly simplify the loading and unloading of film, practically eliminate chances for errors, automatically apprise the camera of the type and speed of film being used, and let the user know both the type of film in the camera and the state of its advancement.